<template>
  <div id="app">
    <div class="container">
      <!-- 顶部框模块 -->
      <div class="form-group">
        <div class="input-group">
          <h4>品牌管理</h4>
        </div>
      </div>

      <!-- 数据表格 -->
      <table class="table table-bordered table-hover mt-2">
        <thead>
          <tr>
            <th>编号</th>
            <th>资产名称</th>
            <th>价格</th>
            <th>创建时间</th>
            <th>操作</th>
          </tr>
        </thead>
        <tbody>
          <tr v-for="item in list" :key="item.id">
            <td>{{item.id}}</td>
            <td>{{item.name}}</td>

            <!-- 如果价格超过100，就有red这个类 -->
            <td :class="{red:item.price>100}">{{item.price}}</td>
            <td>{{forMoment(item.time) }} </td>
            <td><a href="javascript:;" @click="del(item.id)">删除</a></td>
          </tr>
          <tr v-if="!list.length">
             <td colspan="5" style="text-align: center">暂无数据</td>
          </tr>
        </tbody>
          
        <tfoot >
          <tr>
           <td colspan="1">统计：</td>
           <td colspan="2">总价钱为：{{total}}</td>
           <td colspan="2">平均价：{{avg}}</td>
          </tr>
        </tfoot>
           
      </table>

      <!-- 添加资产 -->
      <form class="form-inline">
        <div class="form-group">
          <div class="input-group">
            <input
              type="text"
              class="form-control"
              placeholder="资产名称"
              v-model="name"
               />
          </div>
        </div>
        &nbsp;&nbsp;&nbsp;&nbsp;
        <div class="form-group">
          <div class="input-group">
            <input
              type="number"
              class="form-control"
              placeholder="价格"
              v-model="price"
            />
          </div>
        </div>
        &nbsp;&nbsp;&nbsp;&nbsp;
        <!-- 阻止表单提交 -->
        <button @click.prevent="add" class="btn btn-primary">添加资产</button>
      </form>
    </div>
  </div>
</template>

<script>
    import moment from 'moment'
export default {
  data() {
    return {
      name: "", // 名称
      price: 0, // 价格
      list: JSON.parse(localStorage.getItem('list')),
    };
  },
methods:{
    add(){
    if(this.name==""||this.price<=0){
            return alert('资产名称为空或价格不合理！')
        }
        let id=this.list.length<=0?100 : this.list[this.list.length-1].id+1;
    this.list.push({
        id:id,
        name:this.name,
        price:this.price,
        time:new Date()
    })
    // 清空表单
    this.name=''
    this.price=0
    },
    forMoment(date){
     return   moment(date).format('YYYY-MM-DD')
    },
    del(id){
   let index= this.list.findIndex(ele=>ele.id=id)
   this.list.splice(index,1)
    }
},
computed:{
    total(){
        let num=0
        this.list.forEach(ele=>{
            num+=parseFloat(ele.price) 
        })
        return num
    },
    avg(){
      return  (this.total / this.list.length).toFixed(2)
    }
},
watch:{
  list:{
      deep:true,
      handler(n){
      localStorage.setItem('list',JSON.stringify(this.list))
      }
  }
}
};
</script>

<style >
.red{
  color: red;
}
</style>